US8301276B2ActiveUtilityA1
Control device for the position control of a hydraulic cylinder unit comprising a linearization unit
Est. expiryOct 30, 2027(~1.3 yrs left)· nominal 20-yr term from priority
F15B 9/09F15B 2211/6336G05B 19/291F15B 2211/6656G05B 2219/41309G05B 19/351B21B 37/62G05B 19/231G05B 2219/41124
68
PatentIndex Score
7
Cited by
28
References
18
Claims
Abstract
A control device for the position control of a hydraulic cylinder unit has a controller which receives a set and an actual piston position and determines a preliminary manipulated variable based on the difference of the set and actual positions. A linearization unit multiplies the variable with a linearization factor and outputs it to the valve control unit so that the piston is adjusted at an adjustment speed. The linearization unit determines the factor dynamically as a function of the actual piston position and of working pressures that prevail at both piston sides. The linearization factor is determined such that a ratio of the adjustment speed to the difference of the set and actual positions is independent of the actual position and the working pressures. In the specific case where the controller is configured as a P controller, the order of the controller and the linearization unit can be reversed.
Claims
exact text as granted — not AI-modified1. A control device for the position control of a hydraulic cylinder unit, comprising
a controller which receives, on the input side, a setpoint position of a piston of the hydraulic cylinder unit and an actual position of the piston and determines a preliminary manipulated variable for a valve control unit of the hydraulic cylinder unit on the basis of the difference between the setpoint position and the actual position,
wherein a linearization unit is arranged downstream of the controller and multiplies the preliminary manipulated variable by a linearization factor and outputs the preliminary manipulated variable multiplied by the linearization factor, as the final manipulated variable to the valve control unit, so that the piston is adjusted at an adjustment speed,
wherein the linearization unit determines the linearization factor dynamically as a function of the actual position of the piston, and of working pressures which prevail on both sides of the piston and on the inflow side and outflow side of the valve control unit, and
wherein the linearization unit determines the linearization factor in such a way that a ratio between the adjustment speed and the difference between the setpoint position and actual position is independent of the actual position of the piston and of the working pressures.
2. The control device according to claim 1 , wherein the controller is embodied as a P controller.
3. The control device according to claim 1 , wherein the linearization unit uses, for the determination of the linearization factor, power data of the valve unit as further data, working faces which are effective on both sides of the piston and minimum possible effective volumes on both sides of the piston.
4. The control device according to claim 3 , wherein the linearization unit receives the further data at least partially as parameters.
5. The control device according to claim 3 , wherein the linearization unit determines the linearization factor according to the relationship:
F
=
K
·
AKA
hA
+
AKB
hB
pP
-
pA
pN
·
QNA
hA
+
pB
-
pT
pN
·
QNB
hB
wherein
F is the linearization factor,
K is a freely selectable, constant scaling factor,
AKA is the working face of the piston facing the increasing working volume,
AKB is the working face of the piston facing the decreasing working volume,
pA is the working pressure acting on the working face of the piston facing the increasing working volume,
pB is the working pressure acting on the working face of the piston facing the decreasing working volume,
pP is the working pressure present on the inflow side of the valve control unit,
pT is the working pressure present on the outflow side of the valve control unit,
pN is a nominal pressure of the valve control unit,
QNA is a rated volume flow which flows into the increasing working volume when a difference between the working pressure present on the inflow side of the valve control unit and the working pressure present in the increasing working volume is equal to the nominal pressure,
QNB is a rated volume flow which flows out of the decreasing working volume when a difference between the working pressure present in the decreasing working volume and the working pressure present on the outflow side of the valve control unit is equal to the nominal pressure,
hA is the quotient between the increasing working volume and the working face facing this working volume, wherein the increasing working volume is determined on the basis of the actual position of the piston and the minimum possible effective volume for this side of the piston, and
hB is the quotient between the decreasing working volume and the working face facing the decreasing working volume, wherein the decreasing working volume is determined on the basis of the actual position of the piston and the minimum possible effective volume for this side of the piston.
6. The control device according to claim 1 , wherein the control device is embodied as a control device programmed by a software module.
7. A control device for the position control of a hydraulic cylinder unit, comprising
a controller which is embodied as a P controller and receives, on the input side, a control variable, determines a manipulated variable for a valve control unit of the hydraulic cylinder unit on the basis of the control variable, and outputs the manipulated variable to the valve control unit, so that the piston is adjusted at an adjustment speed,
wherein a linearization unit is arranged upstream of the controller and receives a setpoint position of a piston of the hydraulic cylinder unit and an actual position of the piston, multiplies the difference between said positions by a linearization factor, and outputs the difference, multiplied by the linearization factor, as a control variable to the controller,
wherein the linearization unit determines the linearization factor dynamically as a function of the actual position of the piston, and of working pressures prevailing on both sides of the piston and on the inflow side and outflow side of the valve control unit, and
wherein the linearization unit determines the linearization factor in such a way that a ratio of the adjustment speed with respect to the difference between the setpoint position and actual position of the piston is independent of the actual position of the piston and of the working pressures.
8. The control device according to claim 7 , wherein the linearization unit uses, for the determination of the linearization factor, power data of the valve unit as further data, working faces which are effective on both sides of the piston and minimum possible effective volumes on both sides of the piston.
9. The control device according to claim 8 , wherein the linearization unit receives the further data at least partially as parameters.
10. The control device according to claim 8 , wherein the linearization unit determines the linearization factor according to the relationship:
F
=
K
·
AKA
hA
+
AKB
hB
pP
-
pA
pN
·
QNA
hA
+
pB
-
pT
pN
·
QNB
hB
wherein
F is the linearization factor,
K is a freely selectable, constant scaling factor,
AKA is the working face of the piston facing the increasing working volume,
AKB is the working face of the piston facing the decreasing working volume,
pA is the working pressure acting on the working face of the piston facing the increasing working volume,
pB is the working pressure acting on the working face of the piston facing the decreasing working volume,
pP is the working pressure present on the inflow side of the valve control unit,
pT is the working pressure present on the outflow side of the valve control unit,
pN is a nominal pressure of the valve control unit,
QNA is a rated volume flow which flows into the increasing working volume when a difference between the working pressure present on the inflow side of the valve control unit and the working pressure present in the increasing working volume is equal to the nominal pressure,
QNB is a rated volume flow which flows out of the decreasing working volume when a difference between the working pressure present in the decreasing working volume and the working pressure present on the outflow side of the valve control unit is equal to the nominal pressure,
hA is the quotient between the increasing working volume and the working face facing this working volume, wherein the increasing working volume is determined on the basis of the actual position of the piston and the minimum possible effective volume for this side of the piston, and
hB is the quotient between the decreasing working volume and the working face facing the decreasing working volume, wherein the decreasing working volume is determined on the basis of the actual position of the piston and the minimum possible effective volume for this side of the piston.
11. The control device according to claim 7 , wherein the control device is embodied as a control device programmed by a software module.
12. A method comprising the step of using a hydraulic cylinder unit and controlling the hydraulic cylinder unit by means of a control device for controlling the positioning of a rolling stand, wherein the control device comprises:
a controller which receives, on the input side, a setpoint position of a piston of the hydraulic cylinder unit and an actual position of the piston and determines a preliminary manipulated variable for a valve control unit of the hydraulic cylinder unit on the basis of the difference between the setpoint position and the actual position,
wherein a linearization unit is arranged downstream of the controller and multiplies the preliminary manipulated variable by a linearization factor and outputs the preliminary manipulated variable multiplied by the linearization factor, as the final manipulated variable to the valve control unit, so that the piston is adjusted at an adjustment speed,
wherein the linearization unit determines the linearization factor dynamically as a function of the actual position of the piston, and of working pressures which prevail on both sides of the piston and on the inflow side and outflow side of the valve control unit, and
wherein the linearization unit determines the linearization factor in such a way that a ratio between the adjustment speed and the difference between the setpoint position and actual position is independent of the actual position of the piston and of the working pressures.
13. The method according to claim 12 , wherein the linearization unit uses, for the determination of the linearization factor, power data of the valve unit as further data, working faces which are effective on both sides of the piston and minimum possible effective volumes on both sides of the piston.
14. A method comprising the step of using a hydraulic cylinder unit and controlling the hydraulic cylinder unit by means of a control device for controlling the positioning of a rolling stand, wherein the control device comprises:
a controller which is embodied as a P controller and receives, on the input side, a control variable, determines a manipulated variable for a valve control unit of the hydraulic cylinder unit on the basis of the control variable, and outputs the manipulated variable to the valve control unit, so that the piston is adjusted at an adjustment speed,
wherein a linearization unit is arranged upstream of the controller and receives a setpoint position of a piston of the hydraulic cylinder unit and an actual position of the piston, multiplies the difference between said positions by a linearization factor, and outputs the difference, multiplied by the linearization factor, as a control variable to the controller,
wherein the linearization unit determines the linearization factor dynamically as a function of the actual position of the piston, and of working pressures prevailing on both sides of the piston and on the inflow side and outflow side of the valve control unit, and
wherein the linearization unit determines the linearization factor in such a way that a ratio of the adjustment speed with respect to the difference between the setpoint position and actual position of the piston is independent of the actual position of the piston and of the working pressures.
15. The method according to claim 14 , wherein the linearization unit uses, for the determination of the linearization factor, power data of the valve unit as further data, working faces which are effective on both sides of the piston and minimum possible effective volumes on both sides of the piston.
16. The method according to claim 15 , wherein the linearization unit receives the further data at least partially as parameters.
17. The method according to claim 15 , wherein the linearization unit determines the linearization factor according to the relationship:
F
=
K
·
AKA
hA
+
AKB
hB
pP
-
pA
pN
·
QNA
hA
+
pB
-
pT
pN
·
QNB
hB
wherein
F is the linearization factor,
K is a freely selectable, constant scaling factor,
AKA is the working face of the piston facing the increasing working volume,
AKB is the working face of the piston facing the decreasing working volume,
pA is the working pressure acting on the working face of the piston facing the increasing working volume,
pB is the working pressure acting on the working face of the piston facing the decreasing working volume,
pP is the working pressure present on the inflow side of the valve control unit,
pT is the working pressure present on the outflow side of the valve control unit,
pN is a nominal pressure of the valve control unit,
QNA is a rated volume flow which flows into the increasing working volume when a difference between the working pressure present on the inflow side of the valve control unit and the working pressure present in the increasing working volume is equal to the nominal pressure,
QNB is a rated volume flow which flows out of the decreasing working volume when a difference between the working pressure present in the decreasing working volume and the working pressure present on the outflow side of the valve control unit is equal to the nominal pressure,
hA is the quotient between the increasing working volume and the working face facing this working volume, wherein the increasing working volume is determined on the basis of the actual position of the piston and the minimum possible effective volume for this side of the piston, and
hB is the quotient between the decreasing working volume and the working face facing the decreasing working volume, wherein the decreasing working volume is determined on the basis of the actual position of the piston and the minimum possible effective volume for this side of the piston.
18. The method according to claim 14 , wherein the control device is embodied as a control device programmed by a software module.Join the waitlist — get patent alerts
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